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We present a re-evaluation of the structure function ratios F2(He)/F2(D), F2(C)/F2(D) and F2(Ca)/F2(D) measured in deep inelastic muon-nucleus scattering at an incident muon momentum of 200 GeV. We also present the ratios F2(C)/F2(Li), F2(Ca)/F2(Li) and F2(Ca)/F2(C) measured at 90 GeV. The results are based on data already published by NMC; the main difference in the analysis is a correction for the masses of the deuterium targets and an improvement in the radiative corrections. The kinematic range covered is 0.0035 < x < 0.65, 0.5 < Q^2

A new scaling variable is introduced in terms of which nuclear shadowing in deep-inelastic scattering is universal, i.e. independent of $A$, $Q^2$ and $x$. This variable can be interpreted as a measure of the number of gluons probed by the hadronic fluctuations of a virtual photon during their lifetime. According to recent data from the H1 and ZEUS experiments, the gluon density in a proton rises steeply as $x$ tends to zero. So nuclei which in the infinite momentum frame have a large surface density of gluons model at larger $x$ values what we expect for the proton at much smaller $x$. Using experimental information on nuclear shadowing we predict the unitarity corrections to the proton structure function at small $x$ and extract the bare Pomeron intercept.

We report on the measurement of inclusive electron scattering off a carbon target performed with CLAS at Jefferson Laboratory. A combination of three different beam energies 1.161, 2.261 and 4.461 GeV allowed us to reach an invariant mass of the final-state hadronic system W~2.4 GeV with four-momentum transfers Q2 ranging from 0.2 to 5 GeV2. These data, together with previous measurements of the inclusive electron scattering off proton and deuteron, which cover a similar continuous two-dimensional region of Q2 and Bjorken variable x, permit the study of nuclear modifications of the nucleon structure. By using these, as well as other world data, we evaluated the F2 structure function and its moments. Using an OPE-based twist expansion, we studied the Q2-evolution of the moments, obtaining a separation of the leading-twist and the total higher-twist terms. The carbon-to-deuteron ratio of the leading-twist contributions to the F2 moments exhibits the well known EMC effect, compatible with that discovered previously in x-space. The total higher-twist term in the carbon nucleus appears, although with large systematic uncertainites, to be smaller with respect to the deuteron case for n

Includes bibliographical references and index

We study nuclear effects in the structure function F_3 which describes the parity violating part of the charged-current neuitrino nucleon deep inelastic scattering. Starting from a covariant approach we derive a factorized expression for the nuclear structure function in terms of nuclear spectral function and off-shell nucleon structure functions valid for arbitrary momentum transfer Q and in the limit of weak nuclear binding, i.e. when a nucleus can be treated as a non-relativistic system. We develop a systematic expansion of nuclear structure functions in terms of Q^{-2} series caused by nuclear effects ("nuclear twist" series). Basing on this expansion we calculate nuclear corrections to the Gross-Llewellyn-Smith sum rule as well as to higher moments of F_3. We show that corrections to the GLS sum rule due to nuclear effects cancel out in the Bjorken limit and calculate the corresponding Q^{-2} correction. Special attention is payed to the discussion of the off-shell effects in the structure functions. A sizable impact of these effects both on Q^2- and x-dependence of nuclear structure functions is found.

A detailed NNLO QCD analysis of new CCFR data on the $xF_3$ structure function including the target mass, higher twist and nuclear corrections was performed and parametrizations of the perturbative and power terms of the structure function were constructed. The results of QCD analysis of the structure function were used to study the $Q^2-$dependence of the Gross-Llewellyn Smith sum rule. The $\alpha_S/\pi-$expansion of $S_{GLS}(Q^2)$ was studied and parameters of the expansion were found to be $s_1=2.74\pm 0.01$, $s_2=-2.22\pm 0.23$, $s_3=-7.86\pm 1.74$ in a good agreement with the perturbative QCD predictions for the Gross-Llewellyn Smith sum rule in the next-to-leading and next-to-next-to-leading order.

We consider the effect of nuclear shadowing in polarized deep inelastic scattering (DIS) on ^6LiD at small Bjorken x and its relevance to the extraction of the deuteron spin structure function g_{1}^{d}(x,Q^2). Using models, which describe nuclear shadowing in unpolarized DIS, we demonstrate that the nuclear shadowing correction to g_{1}^{d}(x,Q^2) is significant.

Nuclear effects in Deep Inelastic Scattering of polarized electrons off polarized $^3$He are analyzed in terms of a spin dependent spectral function taking into account $S'$ and $D$ waves in $^3$He, as well as Fermi motion and binding effects. A simple and reliable equation relating the neutron and $^3$He spin structure functions is proposed.

Inclusive electron scattering data are presented for ^2H and Fe targets at an incident electron energy of 4.045 GeV for a range of momentum transfers from Q^2 = 1 to 7 (GeV/c)^2. Data were taken at Jefferson Laboratory for low values of energy loss, corresponding to values of Bjorken x greater than or near 1. The structure functions do not show scaling in x in this range, where inelastic scattering is not expected to dominate the cross section. The data do show scaling, however, in the Nachtmann variable \xi. This scaling may be the result of Bloom Gilman duality in the nucleon structure function combined with the Fermi motion of the nucleons in the nucleus. The resulting extension of scaling to larger values of \xi opens up the possibility of accessing nuclear structure functions in the high-x region at lower values of Q^2 than previously believed.

We present an analysis of the $xF_3(x,Q^2)$ structure function and Gross-Llewellyn Smith(GLS) sum rule taking into account the nuclear effects and higher twist correction. This analysis is based on the results presented in "N. M. Nath et al., Indian J Phys 90(1), 117 (2016)". The corrections due to nuclear effects predicted in several earlier analysis are incorporated to our results of $xF_3(x,Q^2)$ structure function and GLS sum rule for free nucleon, corrected upto next-next-to-leading order (NNLO) perturbative order and calculate the nuclear structure function as well as sum rule for nuclei. In addition, by means of a simple model we have extracted the higher twist contributions to the non-singlet structure function $xF_3(x,Q^2)$ and GLS sum rule in NNLO perturbative orders and then incorporated them to our results. Our NNLO results along with nuclear effect and higher twist corrections are observed to be compatible with corresponding experimental data and other phenomenological analysis.

We analyze the CCFR collaboration iron target data on the xF3 structure function making particular emphasis on the extraction of the higher twist contributions from data. Corrections for nuclear effects are applied in order to extract data on the structure function of the isoscalar nucleon. Our analysis confirms the observation made earlier, that the higher twist terms depend strongly on the level to which QCD perturbation theory analysis is applied. We discuss the impact of nuclear effects on the higher twist term as well as on the QCD scale parameter Lambda_{\bar{MS}} extracted from the fit to data.

We analyze the CCFR collaboration iron target data on the xF3 structure function making particular emphasis on the extraction of the higher twist contributions from data. Corrections for nuclear effects are applied in order to extract data on the structure function of the isoscalar nucleon. Our analysis confirms the observation made earlier, that the higher twist terms depend strongly on the level to which QCD perturbation theory analysis is applied. We discuss the impact of nuclear effects on the higher twist term as well as on the QCD scale parameter Lambda_{\bar{MS}} extracted from the fit to data.

We analyze the CCFR collaboration iron target data on the xF3 structure function making particular emphasis on the extraction of the higher twist contributions from data. Corrections for nuclear effects are applied in order to extract data on the structure function of the isoscalar nucleon. Our analysis confirms the observation made earlier, that the higher twist terms depend strongly on the level to which QCD perturbation theory analysis is applied. We discuss the impact of nuclear effects on the higher twist term as well as on the QCD scale parameter Lambda_{\bar{MS}} extracted from the fit to data.

This work combines the work of four investigators in the Department of Chemistry at the University of Louisville. All of the projects require high-field NMR and other techniques of Structural Biology for their completion. Two high-field NMR spectrometers, one operating at400 MHz and one at 700 MHz, were purchased installed and tested.

This work combines the work of four investigators in the Department of Chemistry at the University of Louisville. All of the projects require high-field NMR and other techniques of Structural Biology for their completion. Two high-field NMR spectrometers, one operating at400 MHz and one at 700 MHz, were purchased installed and tested.

Two High-Field NMR spectrometers supported four research projects: Task 1. Mechanism of conversion of uridine to pseudouridine and to 4-thiouridine. We overexpressed the active C-terminal domain of enzyme ThiI, required for 4-thiouridine modification of tRNA. The two psuedouridine synthetases, TruB and RluA convert uridine to pseudourine in tRNA. We show the two enzymes generate the same products of F5U. Task 2. Devising new nanocomposites that can enhance wound healing. We synthesized MgO nanoparticles and characterized their interactions with ATP. Task 3. Characterization of the complex between Factor XIII and fibrinogen in blood clotting. We have set up the expression system for Fbg alphaC 242-424 in Ecoli. A system that will subsequently be used to purify the expressed protein has been established. Task 4. NMR probes for elastin spectroscopy built and tested. An expression system for heterodimeric collagen has been established. The entropy of water molecules on the surface of elastin has been measured.

Two High-Field NMR spectrometers supported four research projects: Task 1, Mechanism of conversion of uridine to pseudouridine and to 4-thiouridine. We overexpressed the active C-terminal domain of enzyme Thil, required for 4-thiouridine modification of tRNA. The two psuedouridine synthetases, TruB and RluA convert uridine to pseudourine in tRNA. We show the two enzymes generate the same products of F5U. Task 2, Devising new nanocomposites that can enhance wound healing. We synthesized MgO nanoparticles and characterized their interactions with ATP. Task 3, Characterization of the complex between Factor XIII and fibrinogen in blood clotting. We have set up the expression system for Fbg alphaC 242-424 in Ecoli. A system that will subsequently be used to purify the expressed protein has been established. Task 4, NMR probes for elastin spectroscopy built and tested. An expression system for heterodimeric collagen has been established. The entropy of water molecules on the surface of elastin has been measured.